Surfacing film for composites with barrier layer

ABSTRACT

Fiber reinforced resin matrix composite laminates are provided comprising: at least one layer of fiber reinforced resin matrix comprising a cured resin matrix; and a surfacing construction bound to the cured resin matrix and forming a surface of the laminate, comprising: at least one barrier layer; and at least one cured adhesive layer derived from high temperature cure adhesive. In some embodiments, barrier layer(s) may be substantially impermeable to organic solvents, water, and/or gasses. In another aspect, fiber reinforced resin matrix composite laminates are provided comprising: a) at least one layer of fiber reinforced resin matrix comprising a cured resin matrix; and b) a surfacing construction bound to the cured resin matrix and forming a surface of the laminate, comprising: at least one barrier layer; and at least one electrically conductive layer. In another aspect, a surfacing construction is provided comprising a barrier layer and a curable adhesive layer.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 61/122,633, filed Dec. 15, 2008, the disclosure of whichis incorporated by reference herein in it entirety.

FIELD OF THE DISCLOSURE

This disclosure relates to fiber reinforced resin matrix compositelaminates, which include a surfacing construction (surfacing film) whichcomprises at least one barrier layer.

BACKGROUND OF THE DISCLOSURE

The use of fiber reinforced resin matrix or fiber reinforced plastic(FRP) matrix composite laminates (“composites”) has become widelyaccepted for the variety of applications in aerospace, automotive andother transportation industries because their light weight, highstrength and stiffness. Weight reduction benefits and performanceenhancements are the biggest drivers behind implementation of fiberreinforced resin matrix composite laminates into industrialapplications. Various airspace components being manufactured fromfiberglass and carbon fibers reinforced composites including airplanefuselage sections and wing structures. Composites are used to fabricatemany parts for airplanes, wind generators, automobiles, sporting goods,furniture, buses, trucks, boats, train cars and other applications wherestiff, light-weight materials, or consolidation of parts are beneficial.Most often the fibers are made of carbon, glass, ceramic or aramid, andthe resin matrix is an organic thermosetting or thermoplastic material.These parts are typically manufactured under vacuum and/or pressure attemperatures from 20° C. to 180° C., occasionally up to 230° C., andoccasionally up to 360° C.

SUMMARY OF THE DISCLOSURE

Briefly, the present disclosure provides a fiber reinforced resin matrixcomposite laminate comprising: a) at least one layer of fiber reinforcedresin matrix comprising a cured resin matrix; and b) a surfacingconstruction bound to the cured resin matrix and forming a surface ofthe laminate, comprising: i) at least one barrier layer; and ii) atleast one cured adhesive layer derived from high temperature cureadhesive. Typically the cured adhesive layer is bound to the cured resinmatrix. Typically the barrier layer(s) have a composition different fromthat of the cured adhesive layer(s), the barrier layer(s) have acomposition different from that of the cured resin matrix, and the curedadhesive layer(s) have a composition different from that of the resinmatrix. In some embodiments, the one or more barrier layer(s) may besubstantially impermeable to organic solvents, and/or substantiallyimpermeable to water, and/or substantially impermeable to gasses. Insome embodiments, the surfacing construction additionally comprises oneor more of an electrically conductive layer, an EMI shield layer, a UVprotection layer, or a viscoelastic layer. In some embodiments, thebarrier layer may comprise a fluoropolymer, which may be per-fluorinatedand may be non-perfluorinated. In some embodiments, the cured adhesivelayer comprises a dicyandiamide-cured epoxy adhesive. In someembodiments, the cured adhesive layer comprises no cured epoxy adhesivewhich is amine-cured epoxy adhesive.

In another aspect, the present disclosure provides a method of making afiber reinforced resin matrix composite laminate comprising the stepsof: a) providing a curable fiber reinforced resin matrix comprising acurable resin matrix; b) providing a surfacing construction comprising:i) at least one barrier layer; and ii) at least one curable adhesivelayer; c) providing a tool having a shape which is the inverse of thedesired shape of the laminate; e) laying up the surfacing constructionand the curable fiber reinforced resin matrix in the tool, in noparticular chronological order, but with the surfacing construction incontact with the tool and with at least one curable adhesive layer incontact with the curable fiber reinforced resin matrix; and f) curingthe curable resin matrix and curable adhesive layer to make a fiberreinforced resin matrix composite laminate. Typically, the barrierlayer(s) have a composition different from that of the curable adhesivelayer(s) and the barrier layer(s) have a composition different from thatof the cured resin matrix. In some embodiments, at least one curableadhesive layer has a composition different from that of the curableresin matrix. In some embodiments, the one or more barrier layer(s) maybe substantially impermeable to organic solvents, and/or substantiallyimpermeable to water, and/or substantially impermeable to gasses. Insome embodiments, the surfacing construction additionally comprises oneor more of an electrically conductive layer, an EMI shield layer, a UVprotection layer, or a viscoelastic layer. In some embodiments, thebarrier layer may comprise a fluoropolymer, which may be per-fluorinatedand may be non-perfluorinated. In some embodiments, the curable adhesivelayer comprises an epoxy adhesive and a dicyandiamide curative. In someembodiments, the curable adhesive layer comprises no amine-containingcurative. In some embodiments, at least one, and in some cases all,curable adhesive layer(s) have a composition different from that of thecurable resin matrix. In some embodiments, at least one, and in somecases all, curable adhesive layer(s) have a composition which is thesame as that of the curable resin matrix. In some embodiments, at leastone, and in some cases all, curable adhesive layer(s) are the curableresin matrix. In some embodiments, at least one, and in some cases all,curable adhesive layer(s) are not the curable resin matrix.

In another aspect, the present disclosure provides a fiber reinforcedresin matrix composite laminate comprising: a) at least one layer offiber reinforced resin matrix comprising a cured resin matrix; and b) asurfacing construction bound to the cured resin matrix and forming asurface of the laminate, comprising: i) at least one barrier layer; andiii) at least one electrically conductive layer. Typically, the barrierlayer(s) have a composition different from that of the cured resinmatrix. In some embodiments, the one or more barrier layer(s) may besubstantially impermeable to organic solvents, and/or substantiallyimpermeable to water, and/or substantially impermeable to gasses. Insome embodiments, the surfacing construction additionally comprises oneor more of a cured adhesive layer, a UV protection layer, or aviscoelastic layer. In some embodiments, the barrier layer may comprisea fluoropolymer, which may be per-fluorinated and may benon-perfluorinated.

In another aspect, the present disclosure provides a surfacingconstruction comprising at least one barrier layer and at least onecurable adhesive layer. In some embodiments, the one or more barrierlayer(s) may be substantially impermeable to organic solvents, and/orsubstantially impermeable to water, and/or substantially impermeable togasses. In some embodiments, the surfacing construction additionallycomprises one or more of an electrically conductive layer, an EMI shieldlayer, a UV protection layer, or a viscoelastic layer. In someembodiments, the barrier layer may comprise a fluoropolymer, which maybe per-fluorinated and may be non-perfluorinated. In some embodiments,the curable adhesive layer comprises an epoxy adhesive and adicyandiamide curative. In some embodiments, the curable adhesive layercomprises no amine-containing curative.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is schematic depiction of a comparative composite laminate asdescribed in the Examples below.

FIG. 2 is schematic depiction of a comparative composite laminate asdescribed in the Examples below.

FIG. 3 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 4 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 5 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 6 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 7 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 8 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 9 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 10 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 11 is schematic depiction of a comparative composite laminate asdescribed in the Examples below.

FIG. 12 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 13 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 14 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 15 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 16 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

FIG. 17 is schematic depiction of a fiber reinforced resin matrixcomposite laminate including a surfacing construction according to thepresent disclosure, as described in the Examples below.

DETAILED DESCRIPTION

Fiber reinforced resin matrix or fiber reinforced plastic (FRP) matrixcomposite laminates (“composites”) has become widely accepted for thevariety of applications in aerospace, automotive and othertransportation industries because their light weight, high strength andstiffness. However, during cure, pin-holes may form in the surfacelayers of such parts. Such defects adversely affect the appearance ofthe surface and function as a path for unwanted fluids to penetrate anddegrade the performance of the part. These pin-holes must be eliminatedin a separate operation to fill and/or abrade the surface smooth.

During flight aircraft surfaces can build up large amounts of staticcharge. On metal structures this is conducted away by the metal. Oncomposite structures a conductive layer of paint may be applied to thesurface to address this issue. In some embodiments, the compositeaccording to the present disclosure includes a surfacing film whichincludes one or more electrically conductive layers. Typically, such acomposite does not comprise an electrically conductive or staticdissipating coating such as a paint.

Unprotected composite parts can be damaged by UV radiation, e.g.sunlight. To overcome this problem the parts may be protected with a UVprotective coating, paint or covering. In some embodiments, thecomposite according to the present disclosure includes a surfacing filmwhich includes one or more UV absorbing or reflecting layers. Typically,such a composite does not comprise a UV protective coating, paint orcovering and may require no additional protection from exposure to UV orsunlight.

Aluminum or metallic exterior vehicle structures shield interior systemsand payloads from EMI as well as containing internally generated fieldfrom radiating beyond the vehicle. Many composite parts do not providethis same level of shielding as metallic structure. This shielding isoften developed by including a woven metallic fabric of expand metallicfoil in the structure. A conductive barrier layer may eliminate therequirements for such added elements. In some embodiments, the compositeaccording to the present disclosure includes a surfacing film or barrierlayer which includes one or more conductive or EMI blocking layers.Typically, such a composite does not comprise a conductive or EMIblocking layers elsewhere in the composite structure.

The present disclosure provides a surfacing construction which comprisesat least one polymeric barrier layer and at least one curable layer foruse in the manufacture of composite parts, methods of using thesurfacing construction in the manufacture of composite parts, andcomposite parts made with or bearing such surfacing constructions beforeor after cure. The surfacing construction has a thickness of less than10 mil, more typically less than 6 mil, more typically less than 4 mil,more typically less than 3 mil, more typically less 2 mil, moretypically less than 1 mil, in some embodiments less than 0.75 mil, insome embodiments less than 0.60 mil, in some embodiments less than 0.50mil, in some embodiments less than 0.25 mil, in some embodiments lessthan 0.10 mil, in some embodiments less than 0.05 mil, and in someembodiments less than 0.01 mil. The surfacing construction typically hasa thickness of at least 0.001 mil.

Curable Layer

The curable layer of the present disclosure comprises a thermally ormoisture curable adhesive on at least one surface of the barrier layer.Examples of such curable adhesives include epoxy resins (a mixture ofepoxide resin and curing agent), acrylates, cyano-acrylates, andurethanes. The curable adhesives used in the process of the presentdisclosure are non-tacky to the touch after curing and arethermosetting, that is cure through the action of heat, catalysts, UVlight, and the like. Epoxide resins useful in the protective articles ofthis disclosure are any organic compounds having at least one oxiranering, that is, polymerizable by a ring opening reaction. Such materials,broadly called epoxides, include both monomeric and polymeric epoxidesand can be aliphatic, heterocyclic, cycloaliphatic, or aromatic and canbe combinations thereof. They can be liquid or solid or blends thereof,blends being useful in providing tacky adhesive films prior to cure.These materials generally have, on the average, at least two epoxygroups per molecule and are also called “polyepoxides.” The polymericepoxides include linear polymers having terminal epoxy groups (forexample, a diglyciclyl ether of a polyoxyalkylene glycol), polymershaving skeletal oxirane units (for example, polybutadiene polyepoxide),and polymers having pendent epoxy groups (for example, a glycidylmethacrylate polymer or copolymer). The molecular weight of the epoxyresin may vary from about 74 to about 100,000 or more. Useful epoxideresins include those which contain cyclohexene oxide groups such as theepoxycyclohexane carboxylates, typified by3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate,3,4-epoxy-2-n˜ethylcyclohexylmethyl-3,4-epoxy-2-methycyclohexanecarboxylate, and bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate. For amore detailed list of useful epoxides of this nature, reference may bemade to U.S. Pat. No. 3,117,099. Further epoxide resins which areparticularly useful in the practice of this disclosure include glycidylether monomers of the formula:

where R′ is aliphatic, for example, alkyl; aromatic, for example, uyl;or combinations thereof, and n is an integer of 1 to 6. Examples are theglycidyl ethers of polyhydric phenols such as the diglycidyl ether of2,2-bis-(4-hydroxyphenol)propane (Bisphenol A) and copolymers of(chloromethyl)oxirane and 4,4′-(1-n1et1˜ylethylidene)bisphenol. Furtherexamples of epoxides of this type which can be used in the practice ofthis disclosure are described in U.S. Pat. No. 3,018,262.

There are a host of commercially available epoxide resins that can beused in this disclosure. In particular, epoxides which are readilyavailable include styrene oxide, vinylcyclohexene oxide, glycidol,glycidyl methacrylate, diglycidyl ether of Bisphenol A (for example,those available under the trade designations “EPON S28”, “EPON 1004”, 5and “EPON 1001F from Shell Chemical Company, and “DER-332” and“DER-334”, from Dow Chemical Company), diglycidyl ether of Bisphenol F(for example, those under the trade designations “ARALDITE GY28 1” fromCiba-Geigy Corporation, and “EPON 862” from Shell Chemical Company),vinylcyclohexane dioxide (for example, having the trade designation“ERL-4206” from Union Carbide Corporation),3,4-epoxycyclohexyl-methyl-3,4-epoxycyclohexene carboxylate (forexample, having the trade designation “ERL-4221” from Union CarbideCorporation), 2-(3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy)cyclohexane-metadioxane (for example, having the trade designation“ERL-4234” from Union Carbide Corporation), bis(3,4-epoxycyclohexyl)adipate (for example, having the trade designation “ERL-4299” from UnionCarbide Corporation), dipentene dioxide (for example, having the tradedesignation “ERL-4269” from Union Carbide Corporation), epoxidizedpolybutadiene (for example, having the trade designation “OXIRON 2001”from FMC Corporation), flame retardant epoxide resins (for example,having the trade designation “DER-542”, a brominated bisphenol typeepoxy resin available from Dow Chemical Company), 1,4-butanedioldiglycidyl ether (for example, having the trade designation “ARALDITERD-2” from Ciba-Geigy Corporation), diglycidyl ether of hydrogenatedBisphenol A based epoxide resins (for example, having the tradedesignation “EPONEX 1510 from Shell Chemical Company), and polyglycidylether of phenol-formaldehyde novolak (for example, having the tradedesignations “DEN-43 1” and “DEN-438” from Dow Chemical Company)

The term “Curing agent” is used broadly to include not only thosematerials that are conventionally regarded as curing agents but alsothose materials that catalyze epoxy polymerization as well as thosematerials that may act as both curing agent and catalyst. Preferredcuring agents for the epoxide resin include, for example, roomtemperature curing agents, heat-activated curing agents, andcombinations thereof, and photolytically activated curing agents. Roomtemperature curing agents and heat-activated curing agents can include,for example, blends of epoxy homopolymerization type curing agents andaddition type curing agents. The curing agents preferably react attemperatures of between about room temperature and about 200° C., morepreferably about room temperature and 150° C., even more preferablybetween about room temperature and about 115° C. If the curing agentsare used in epoxy resins that are used to make prepregs to makecomposite articles, then the curing agents preferably react attemperatures in the range of about 200° F. (93° C.) to about 450° F.(230° C.).

The surfacing construction may comprise any suitable curable layer,including in some embodiments those disclosed in U.S. patent applicationSer. No. 11/059,834, filed Feb. 17, 2005, or U.S. Provisional Pat. App.No. 61/118,242, filed Nov. 26, 2008, the disclosures of which areincorporated herein by reference. Such layers may include: 3M™Scotch-Weld™ Structural Adhesive Film AF163-2, 3M™ Scotch-Weld™Structural Adhesive Film AF163-2LS, 3M™ Scotch-Weld™ Structural AdhesiveFilm AF163-2XS, 3M™ Scotch-Weld™ Structural Adhesive Film AF191, 3M™Scotch-Weld™ Structural Adhesive Film AF191XS, 3M™ Scotch-Weld™ LowDensity Composite Surfacing Film AF 325LS, 3M™ Scotch-Weld™ Low DensityComposite Surfacing Film AF 325, Cytec FM 300LS, Cytec 1515-3LS, HenkelPL 793LS, Henkel Synskin™, Cytec Surface Master™ 905, Cytec SurfaceMaster™ 905LS, and layers having similar composition.

In some embodiments, the curable adhesive is not a pressure sensitiveadhesive.

In some embodiments, the curable adhesive is a high temperature cureadhesive. In some embodiments, a high temperature cure adhesive is onewhich cures in less than 6 hours at a temperature of greater than T andfails to cure in 48 hours at a temperature of less than t, where T is insome embodiments 80° C., in some embodiments 100° C., in someembodiments 120° C., and in some embodiments 180° C., and where t is insome embodiments 25° C., in some embodiments 35° C., and in someembodiments 50° C. In some embodiments, a high temperature cure adhesiveis one having temperature-dependent cure characteristics similar tothose of composite matrix resins typically cured at >80° C., in someembodiments similar to within 10% change in temperature, in someembodiments similar to within 20% change in temperature, and in someembodiments similar to within 30% change in temperature.

In some embodiments, the curable layer includes a curative or curingagent. Any suitable curative agent may be used. In some embodiments, thecurative agent may include dicyandiamide. In some embodiments, thecurative agent is dicyandiamide. In some embodiments, the curative agentmay exclude amine curatives. Commercially available examples of curableadhesives which includes dicyandiamide curative include 3M™ Scotch-Weld™Structural Adhesive Film AF 555 and 3M™ Scotch-Weld™ Structural AdhesiveFilm AF 191.

Barrier Layer

The surfacing construction may comprise any suitable polymeric barrierlayer, including in some embodiments partially or fully cured layers ofthe curable layers described above. In some embodiments, the polymericbarrier layer may be selected from polyurethanes, polyureas, polyesters,polyimides, polybutadienes, elastomers, epoxies, fluoropolymers,polycarbonates, mixtures of the above. In some embodiments the polymericbarrier layer is the same polymer as the curable layer. In someembodiments the polymeric barrier layer is a different polymer from thecurable layer. In some embodiments the polymeric barrier layer includesa crosslinked polymer.

Any suitable barrier layer may be used. In some embodiments, thepolymeric barrier layer may be selected from polyurethanes, polyureas,polyesters, polyimides, polybutadienes, elastomers, epoxies,fluoropolymers, polycarbonates, mixtures of the above. Typically thepolymeric barrier layer is of a material that can be used to manufactureparts that are cured or formed under vacuum and/or pressure attemperatures from 20° C. to 180° C. without excessive flow or loss ofintegrity. In some embodiments the polymeric barrier layer is fullycured. In some embodiments the polymeric barrier layer is partiallycured, typically at least 50% cured, more typically at least 60% cured,more typically at least 70% cured, more typically at least 80% cured,and more typically at least 90% cured. In some embodiments the polymericbarrier layer is thermoplastic. Each barrier layer typically has athickness of less than 10 mil, more typically less than 6 mil, moretypically less than 4 mil, more typically less than 3 mil, moretypically less 2 mil, more typically less than 1 mil, in someembodiments less than 0.75 mil, in some embodiments less than 0.60 mil,in some embodiments less than 0.50 mil, in some embodiments less than0.25 mil, in some embodiments less than 0.10 mil, in some embodimentsless than 0.05 mil, and in some embodiments less than 0.01 mil. Eachbarrier layer typically has a thickness of at least 0.001 mil. Typicallythe barrier layer is substantially impermeable to gasses. More typicallythe barrier layer remains substantially impermeable to gasses throughoutthe process of manufacturing a composite of which it is a part. In someembodiments, substantially impermeable to gasses means having an oxygenpermeability of less than 35 cm³-mm/m²/day/atm. Typically the barrierlayer is substantially impermeable to moisture. More typically thebarrier layer remains substantially impermeable to moisture throughoutthe process of manufacturing a composite of which it is a part. In someembodiments, substantially impermeable to moisture means having amoisture vapor transmission rate of less than 30 gm/m²/day. Typicallythe barrier layer is substantially impermeable to organic solvents. Moretypically the barrier layer remains substantially impermeable to organicsolvents throughout the process of manufacturing a composite of which itis a part. In some embodiments, such organic solvents may include fuels,aircraft fuels, lubricants, hydraulic fluids, and the like. In someembodiments, substantially impermeable to an organic solvent meansexhibiting less than 10% weight gain or loss after 7 days exposure tothe solvent at 21° C. and 1 atmosphere. In some embodiments,substantially impermeable to organic solvents means exhibiting less than10% weight gain or loss after 7 days exposure to methylene chloride at21° C. and 1 atmosphere. In some embodiments, substantially impermeableto organic solvents means exhibiting less than 10% weight gain or lossafter 7 days exposure to benzyl alcohol at 21° C. and 1 atmosphere. Insome embodiments, substantially impermeable to organic solvents meansexhibiting less than 10% weight gain or loss after 7 days exposure togasoline at 21° C. and 1 atmosphere. In some embodiments, the barrierlayer is electrically non-conductive. More typically the barrier layerremains electrically non-conductive throughout the process ofmanufacturing a composite of which it is a part. The barrier layeroptionally includes flame retardant ingredients or additives.

In some embodiments, barrier layers may comprise materials such aspolyethylene, polyurethane, polycarbonate and polyimide films includingKapton™ available from DuPont Films, Buffalo, N.Y. The barrier layersmay be clear and colorless, or include a colorant, such as a pigment ordye as the application requires. The barrier layer may be alloys ofthese materials and optionally include flame retardant ingredients orother additives, such as a polyurethane/polycarbonate blend resin withUV absorbers available as U933 from Alberdingk Boley GmbH, Krefeld,Germany.

In some embodiments, barrier layers may comprise materials such asfluorinated polymers. In some embodiments, barrier layers may compriseperfluorinated fluoropolymers, which may include FEP, PFA or PTFEpolymers, including those available from Dyneon. In some embodiments,barrier layers may comprise non-perfluorinated fluoropolymers, such aspolymer which may include interpolymerized units derived from vinylidenefluoride (VDF). Such materials typically include at least about 3 weightpercent of interpolymerized units derived from VDF, which may behomopolymers or copolymers with other ethylenically unsaturatedmonomers, such as hexafluoropropylene (HFP), tetrafluoroethylene (TFE),chlorotrifluoroethylene (CTFE), 2-chloropentafluoropropene,perfluoroalkyl vinylethers, perfluorodiallylether,perfluoro-1,3-butadiene, and/or other perhalogenated monomers andfurther derived from one or more hydrogen-containing and/ornon-fluorinated olefinically unsaturated monomers. Suchfluorine-containing monomers may also be copolymerized withfluorine-free terminally unsaturated olefinic comonomers, such asethylene or propylene. Useful olefinically unsaturated monomers mayinclude alkylene monomers such as 1-hydropentafluoropropene,2-hydropentafluoropropene, etc. Such fluoropolymers may includetetrafluoroethylene-hexafluoropropylene-vinylidene fluoride terpolymersand hexafluoropropylene-vinylidene fluoride copolymers. Commerciallyavailable fluoropolymer materials which may be useful may include, forexample, THV 200, THV 400, and THV 500 fluoropolymers, which areavailable from Dyneon LLC of Oakdale, Minn., and SOLEF 11010 and SOLEF11008, which are available from Solvay Polymers Inc., Houston, Tex.,KYNAR® and KYNAR FLEX® PVDF which are available from Arkema Inc.,Philadelphia, Pa., and TEFZEL LZ300 fluoropolymers, which are availablefrom DuPont Films, Buffalo, N.Y. Additional commercially availablefluoroelastomer materials of this type include, for example, FC-2145,FC-2178, FC-2210X, FC-2211, FC-2230 which are available from Dyneon LLCof Oakdale, Minn., and Technoflon® fluoroelastomers which are availablefrom Solvay Polymers Inc., Houston, Tex. Other useful fluorinatedpolymers, may include non-perfluorinated polymers, which may includepoly(vinylfluoride), such as TEDLAR TAW15AHS, which is available fromDuPont Films of Buffalo, N.Y. Blends of fluoropolymers can also be usedto make the barrier layers of the present disclosure. Commerciallyavailable fluoropolymer materials of this type include, for example,polyvinylidene fluoride alloy films available as DX Film from DenkiKagaku Kogyo Kabushiki Kaisha, Tokyo, JAPAN. Blends of two differenttypes of non-perfluorinated fluoropolymers may be useful, as well asblends of a non-perfluorinated fluoropolymer with a perfluorinatedfluoropolymer. Furthermore, blends of fluoropolymers withnonfluoropolymers, such as polyurethane and polyethylene, for example,can also be used.

Barrier layers for use in the present disclosure can be made by anysuitable method, which may include cast and extrusion methods.

In some embodiments, barrier layers may be clear and colorless, or mayinclude a colorant, such as a pigment or dye as the application desires.Typically, the colorant is an inorganic pigment, such as those disclosedin U.S. Pat. No. 5,132,164. In some embodiments, the pigment may beincorporated into one or more nonfluorinated polymers, which can beblended with one or more fluorinated polymers. In some embodiments, thebarrier layers may be finish and/or color-matched to existing appliquéor paint color schemes.

Optionally, at least one of the surfaces may be treated to allow forbonding of adjacent layers. Such treatment methods include coronatreatment, particularly corona discharge in an atmosphere containingnitrogen, and about 0.1 to about 10 volume percent of an additive gasselected from the group consisting of hydrogen, ammonia, and mixturesthereof, as disclosed in U.S. Pat. No. 5,972,176 (Kirk et al.). Anotheruseful treatment method includes a chemical etch using sodiumnaphthalenide. Such treatment methods are disclosed in Polymer Interfaceand Adhesion, Souheng Wu, Ed., Marcel Dekker, Inc., NY and Basel, pp.279-336 (1982), and Encyclopedia of Polymer Science and Engineering,Second Edition, Supplemental Volume, John Wiley & Sons, pp. 674-689(1989).

Another useful treatment method is the FLUOROETCH process, availablefrom Acton Industries, Inc., Pittston, Pa. Other useful treatments forsurface modification of fluoropolymers include methods that expose alight absorbing electron donor to actinic radiation in the presence of afluoropolymer such as those disclosed in U.S. Pat. No. 6,630,047 (Jinget al.) and U.S. Pat. No. 6,685,793 (Jing). Other treatment methodsinclude the use of such materials as primers. These may be employedeither in place of, or in addition to the surface treatments describedabove. An example of a useful primer is ADHESION PROMOTER #86A (a liquidprimer, available from Minnesota Mining and Manufacturing Company, St.Paul, Minn.).

Surfacing Construction

A surfacing construction according to the present disclosure may be madeby any suitable method. Typically, one or more curable layers and one ormore barrier layers are joined by any suitable method, includinglamination, adhesive bonding by addition of an adhesive layer, adhesivebonding by the adhesive properties of the barrier or curable layer(s)themselves, or the like. Typically, the layers of the surfacingconstruction are joined prior to use in manufacture of a compositearticle, however, in some embodiments the layers become joined duringmanufacture of a composite article. In some embodiments, a singlematerial may perform as both barrier layer and curable layer. Some suchembodiments may comprise a single layer of material. In someembodiments, barrier layer(s) and curable layer(s) are differentmaterials.

In some embodiments, the surfacing construction (surfacing film) maycomprise a single polymeric barrier layer and a single curable layer. Insome embodiments, the surfacing construction may comprise multiplealternating barrier layers and curable layers. In some embodiments, thesurfacing construction may comprise more than one polymeric barrierlayer. In some embodiments, the surfacing construction may comprise morethan one curable layer. In some embodiments, a curable layer of thesurfacing construction is adjacent to the composite in the manufactureof a composite part comprising the surfacing construction. In someembodiments, a curable layer of the surfacing construction isimmediately adjacent to the composite in the manufacture of a compositepart comprising the surfacing construction.

In some embodiments, the surfacing construction may additionallycomprise one or more electrically conductive layers, typically metallayers, which may optionally be a foil, expanded foil, mesh, cloth,paper, wires, or the like. In some embodiments, the electricallyconductive layer or layers are sandwiched between barrier layers. Insome embodiments, the electrically conductive layer or layers arecontained within barrier layers. In some embodiments the electricallyconductive layer or layers are adjacent to the barrier layer. In someembodiments the electrically conductive layer or layers are immediatelyadjacent to the barrier layer.

In some embodiments, the surfacing construction may additionallycomprise one or more layers of functional materials such as radiationabsorbing materials, EMI blocking materials, radiation reflectingmaterials or viscoelastic layers. Such materials may include materialsdisclosed in U.S. patent application Ser. No. 12/255,025, filed on Oct.21, 2008, based on priority application 60/983,781 filed, Oct. 30, 2007,the disclosure of which is incorporated herein by reference. Suchmaterials may include 3M™ Transparent Electrically Conductive AdhesiveFilms (3M Company, St. Paul, Minn.). Viscoelastic materials which may beuseful may include those disclosed in U.S. Pat. Pub. No. 2008/0139722,U.S. patent application Ser. No. 11/952,192, filed Dec. 7, 2007, thedisclosure of which is incorporated herein by reference. Viscoelasticmaterials and viscoelastic constructions which may be included in thesurfacing construction may include those described in U.S. patentapplication Ser. No. ______, filed on even date herewith (Atty Docket#65028US005), the disclosure of which is incorporated herein byreference. Materials which may be useful may include 3M™ ViscoelasticDamping Polymers Type 830 (3M Company, St. Paul, Minn., USA).

In some embodiments, the functional layer or layers are sandwichedbetween barrier layers. In some embodiments, the functional layer orlayers are contained within one or more barrier layers. In someembodiments, the functional layer or layers are adjacent to one or morebarrier layers. In some embodiments, the functional layer or layers areimmediately adjacent to one or more barrier layers.

In some embodiments, the surfacing construction does not comprise fillermaterials. In some embodiments, the surfacing construction does notcomprise inorganic filler materials. In some embodiments, the surfacingconstruction does not comprise organic filler materials. In someembodiments, the surfacing construction does not comprise fibrous fillermaterials. In some embodiments, the surfacing construction does notcomprise non-fibrous filler materials. In some embodiments, thesurfacing construction does not comprise particulate filler materials.In some embodiments, the surfacing construction does not comprise anyfibrous scrim, such as a woven scrim or a non-woven scrim. In someembodiments, the composite part does not comprise a surface fibrousscrim, such as a woven scrim or a non-woven scrim. In some embodiments,the composite part does not comprise an electrically conductive orstatic dissipating coating such as a paint.

Composite Article

A composite article according to the present disclosure may be made byany suitable method. Typically, curable fiber reinforced resin matrixprepregs are used, however, in other embodiments resin matrix and fiberreinforcement may be combined in manufacture of the composite article.Any suitable fiber or matrix materials may be used, many of which areknown in the art. Typically, a mold or form designated a tool is used,the tool having a shape which is the inverse of the desired shape of thelaminate. Typically the surfacing construction is laid up in the tool,or components thereof, followed by one or more curable fiber reinforcedresin matrixes and, in some embodiments, core layer(s) such as foam,wood, or honeycomb construction core layer(s). Thereafter the lay-up iscured by methods known in the art.

In some embodiments, the composite article additionally comprises atleast one core layer. In some embodiments, the core layer may comprisefoam, wood, or honeycomb construction. Such core layers may be laid upbetween curable fiber reinforced resin matrix layers in the manufactureof a composite article. In some embodiments, the layered articlecomprises no such a core layer.

Objects and advantages of this disclosure are further illustrated by thefollowing examples, but the particular materials and amounts thereofrecited in these examples, as well as other conditions and details,should not be construed to unduly limit this disclosure.

Examples

Unless otherwise noted, all reagents were obtained or are available fromAldrich Chemical Co., Milwaukee, Wis., or may be synthesized by knownmethods.

Methods General Tooling and Bagging of a Composite Part

A composite specimen with a curable epoxy adhesive resin was preparedfor curing in the following manner. A flat tool was fabricated bytrimming to 2 ft×2 ft a 12 gauge stainless steel alloy 304 with 2Bfinish. A 1 mil PTFE non-perforated parting film (available as HTF-621from Northern Fiber Glass Sales, Inc.) was applied to the tool andaffixed thereon with heat resistant tape applied at the edges andcorners of the film. Each layer of material was applied to the tool inthe order and arrangement described in the example text. Each layer wasapplied first to the tool, then one upon the other without liners byhand and each layer was consolidated with the previous layer(s) bypassing a 1.5 inch diameter wooden roller over the upper-most layerwhile applying hand pressure to the roller. After every forth ply, thepart and tool were covered with a layer of perforated parting filmdescribed below and then a layer of breather ply described below and thepart was compacted to the tool under full vacuum in a Scotchlite VacuumApplicator Model VAL-1 manufactured by 3M for 3 minutes after which timethe breather ply and perforated parting film were removed and additionalplies were added to the part. Each coupon was permanent marked byapplying a unique identifier along one edge of the part on the exposedface of the part using a Pilot Silver Marker. A perforated parting filmavailable as A5000 from Richmond Aircraft Products was appliedwrinkle-free so as to completely cover the exposed face of the coupon. 1thermocouple was attached to the tool within 2 inches of the coupon. Alayer of non-perforated parting film was applied to the bed of theautoclave described below to cover the area where the tools were placed.The tool and part were placed on the bed of the autoclave describedbelow and a continuous bead of vacuum bag sealing tape was applieddirectly to the bed of the autoclave so that the distance from the tapeto the tool was at least 3 inches. The exposed non-perforated partingfilm on the bed of the autoclave was folded or trimmed clear of thevacuum bag sealing tape. A non-woven polyester 10 oz/yd² felt breatherply (available as RC-3000-10 from Richmond Aircraft Products) wasoverlaid upon the part and the tool and onto the bed of the autoclavesuch that it extended to within 2 inches of the vacuum bag sealing tapeon all sides. A 3 mil high temperature nylon bagging film (available asHS8171 from Richmond Aircraft Products) was placed loosely over the bedof the autoclave to cover the part and tools and to extend to or beyondthe vacuum bag sealing tape on all sides. At least 1 vacuum portassembly was installed in the vacuum bag over the breather ply and thevacuum bag was sealed to the bed of the autoclave along all edges bypressing the film against the vacuum bag seal tape.

High Pressure Curing of a Composite Part

A composite specimen with a curable epoxy adhesive resin was cured inthe following manner. Each composite specimen with a curable epoxyadhesive resin was prepared for curing according to “General Tooling andBagging of a Composite Part”. The vacuum port assembly(ies) was attachedto the vacuum system in the autoclave described below and the parts,tools, parting films and breather plies were consolidated under fullvacuum for 5 minutes. The thermocouples were attached to the controlsystem in the autoclave. The part was then cured under controlledtemperature and pressure conditions in one of two autoclaves, one madeby Thermal Equipment Corporation or the other made by ASC ProcessSystems, using pressure and temperature profiles described below. Thepressure inside the autoclave was increased to 60 psi and the vacuum tothe vacuum port assemblies was removed when the pressure in theautoclave reached 15 psi and the temperature was increased at 5°F./minute until the temperature of the lagging thermocouple reached 177°C. The pressure was maintained between 60 psi and 70 psi and thetemperature was maintained between 177° C. and 182° C. for 120 minutes.The temperature was reduced at a controlled rate of 5° F./minute untilthe temperature of the lagging thermocouple reached 44° C. The pressurewas maintained between 60 psi and 70 psi until the temperature of thelagging thermocouple reached 66° C., then the pressure in the autoclavewas vented to the atmosphere. The cured composite specimen was removedfrom the autoclave, bagging and tool.

Low Pressure 1½ Hour Curing of a Composite Part

A composite specimen with a curable epoxy adhesive resin was cured inthe following manner. Each composite specimen with a curable epoxyadhesive resin was prepared for curing according to “General Tooling andBagging of a Composite Part”. The vacuum port assembly(ies) was attachedto the vacuum system in the autoclave described below and the parts,tools, parting films and breather plies were consolidated under fullvacuum for 5 minutes. The thermocouples were attached to the controlsystem in the autoclave. The part was then cured under controlledtemperature and pressure conditions in one of two autoclaves, one madeby Thermal Equipment Corporation or the other made by ASC ProcessSystems, using pressure and temperature profiles described below. Thepressure inside the autoclave was increased to 45 psi and the vacuum tothe vacuum port assemblies was removed when the pressure in theautoclave reached 15 psi and the temperature was increased at 5°F./minute until the temperature of the lagging thermocouple reached 177°C. The pressure was maintained between 40 psi and 50 psi and thetemperature was maintained between 177° C. and 182° C. for 90 minutes.The temperature was reduced at a controlled rate of 5° F./minute untilthe temperature of the lagging thermocouple reached 44° C. The pressurewas maintained between 40 psi and 50 psi until the temperature of thelagging thermocouple reached 66° C., then the pressure in the autoclavewas vented to the atmosphere. The cured composite specimen was removedfrom the autoclave, bagging and tool.

Low Pressure 2 Hour Curing of a Composite Part

A composite specimen with a curable epoxy adhesive resin was cured inthe following manner. Each composite specimen with a curable epoxyadhesive resin was prepared for curing according to “General Tooling andBagging of a Composite Part”. The vacuum port assembly(ies) was attachedto the vacuum system in the autoclave described below and the parts,tools, parting films and breather plies were consolidated under fullvacuum for 5 minutes. The thermocouples were attached to the controlsystem in the autoclave. The part was then cured under controlledtemperature and pressure conditions in one of two autoclaves, one madeby Thermal Equipment Corporation or the other made by ASC ProcessSystems, using pressure and temperature profiles described below. Thepressure inside the autoclave was increased to 45 psi and the vacuum tothe vacuum port assemblies was removed when the pressure in theautoclave reached 15 psi and the temperature was increased at 5°F./minute until the temperature of the lagging thermocouple reached 177°C. The pressure was maintained between 40 psi and 50 psi and thetemperature was maintained between 177° C. and 182° C. for 120 minutes.The temperature was reduced at a controlled rate of 5° F./minute untilthe temperature of the lagging thermocouple reached 44° C. The pressurewas maintained between 40 psi and 50 psi until the temperature of thelagging thermocouple reached 66° C., then the pressure in the autoclavewas vented to the atmosphere. The cured composite specimen was removedfrom the autoclave, bagging and tool.

General Laminating

Layers in the construction were brought together in combinations, orderand quantities as described below. Removable carriers were separatedfrom mating surfaces during the laminating process. These layers werelaminated by feeding them at a rate of 2.5 ft/min into the nip of aGeppert Engineering Inc. laminator using 4 inch rubber rollers a ambientconditions (22° C.; 50 percent Relative Humidity).

Intermediate Assembly Examples Polyurethane/Polycarbonate Barrier Layer,200

A polyurethane/polycarbonate barrier layer was provided in the followingmanner. A polymer solution was prepared. More specifically, 100 parts oftransparent polyurethane/polycarbonate resin with 3% UV Absorberavailable as U933 from Alberdingk, and 1.5 parts polyfunctionalaziridine crosslinker available as Neocryl CX-100 from Neoresins Inc.were added to a one liter, narrow-mouthed bottle. The solution was mixedby stirring with a wooden tongue depressor for 3 minutes at ambientconditions (22° C.; 50 percent Relative Humidity). The final polymersolution was then poured onto the surface of an untreated 2 miltransparent polyester film, and coated using a knife-over-bed coatingstation. The gap between knife and bed was set to be 1.5 mils greaterthan the thickness of the polyester carrier web. The coated backing wasdried at 55° C. for 1 hour in a 9 ft³ vented recirculating ovenmanufactured by the Dispatch Oven Company. After drying, the thicknessof the polyurethane/polycarbonate film was approximately 0.5 mil. Atransparent UV absorbing polyurethane/polycarbonate film borne onpolyester film was obtained.

Fluoropolymer Barrier Layer, 208

Several fluoropolymer films were provided or cast at approximately 1 milthickness and used to make examples. These films included:

-   -   Dyneon™ Fluorothermoplastic THV500 from Dyneon™    -   Dyneon™ Fluoroplastic PVDF 11010/0000 polyvinylidene fluoride        from Dyneon™    -   Dyneon™ Fluoroplastic PVDF 11008/0001 polyvinylidene fluoride        from Dyneon™    -   Solef® 11010 polyvinylidene fluoride from Solvay Solexis.    -   Dyneon™ Fluoroplastic PVDF 11010/0000 polyvinylidene fluoride        from Dyneon™ combined with Polymethyl Methacrylate (PMMA),        available broadly, at 90/10, 80/20, 75/25, 60/40, and 50/50% by        weight.

Conductive Fluoropolymer Barrier Layer, 513

Several fluoropolymer films were provided or cast with conductiveadditives to approximately 1 mil thickness and used to make examples.These films included:

-   -   Dyneon™ Fluorothermoplastic THV510ESD from Dyneon™    -   Dyneon™ Fluorothermoplastic THV500 from Dyneon™ combined with        Baytubes® C150HP multiwalled carbon nano-tubes from Bayer at        98/2% by weight.    -   Dyneon™ Fluoroplastic PVDF 11010/0000 polyvinylidene fluoride        from Dyneon™ combined with Baytubes® C150HP multiwalled carbon        nano-tubes from Bayer at 98/2, and 99.25/0.25% by weight.        Viscoelastic Construction with a Barrier Layer Each Side of        Viscoelastic Material (VEM) Layer, 10

With reference to the FIG. 8, a viscoelastic material 300 and apolyurethane/polycarbonate barrier layer 200 were provided and used toprepare a modified viscoelastic construction 10, such as described moregenerally in U.S. patent application Ser. No. ______, filed on even dateherewith (Atty Docket #65028US005), the disclosure of which isincorporated herein by reference. More specifically, the followingmaterials were assembled and laminated as described in “GeneralLaminating” above. First, a ½ mil thick polyurethane/polycarbonatebarrier layer 200 per “Polyurethane/Polycarbonate Barrier Layer” above,borne on a polyester film (not shown) was joined to one side of a 2 milthick viscoelastic damping polymer 300, available as 3M™ ViscoelasticDamping Polymers Type 830 from 3M Company, which has a peak dampingratio (Tan δ) of greater than 1.0 as measured in shear mode by DMTA at10 Hz. To the other side of the 2 mils viscoelastic damping polymer 300was joined another ½ mil thick polyurethane/polycarbonate barrier layer200 per “Polyurethane/Polycarbonate Barrier Layer” above. All remainingliners and carriers were removed, including polyester films, providing a3 mil thick modified viscoelastic construction 10. The character of theviscous-elastic material 300 was to be easily torn by hand, unable tosupport itself in a free-standing state, and very tacky at ambientconditions (22° C.; 50 percent Relative Humidity). The character of themodified viscoelastic construction 10 was to be very elastic, film-likein the free standing state, and lacking tack at ambient conditions (22°C.; 50 percent Relative Humidity). A non-tacky, stiffened, viscoelasticconstruction was obtained.

Barrier Modified Surfacing Film 20

With reference to the FIG. 3, structural adhesive film 401 andpolyurethane/polycarbonate barrier layer 200 were provided and used toprepare barrier modified surfacing film 20. More specifically, thefollowing materials were assembled and laminated as described in“General Laminating” above. A ½ mil thick polyurethane/polycarbonatebarrier layer 200 prepared as described above was joined to one side ofan 8 mil thick epoxy structural adhesive film 401 which includes anon-woven polyester veil at 0.05 lbs./sqft available as 3M™ Scotch-Weld™Structural Adhesive Film AF 555M from 3M Company. Remaining liners andcarriers were removed, including polyester films, providing an 8.5 milthick barrier modified surfacing film 20, which is a UV blockingsurfacing film with a high temperature structural adhesive film and athinner cured barrier layer.

Barrier Modified Surfacing Film 24

With reference to FIG. 4, structural adhesive film 402 andpolyurethane/polycarbonate barrier layer 200 were provided and used toprepare barrier modified surfacing film 24. More specifically, thefollowing materials were assembled and laminated as described in“General Laminating” above. A ½ mil thick polyurethane/polycarbonatebarrier layer 200 prepared as described above was joined to one side ofa 13 mil thick epoxy structural adhesive film 402 which includes a knitnylon veil at 0.085 lbs./sqft available as 3M™ Scotch-Weld™ StructuralAdhesive Film AF 500K from 3M Company. Remaining liners and carrierswere removed, including polyester films, providing a 13.5 mil thickbarrier modified surfacing film 24, which is a transparent UV blockingsurfacing film with a low temperature structural adhesive film and athinner cured barrier layer.

Barrier Modified Surfacing Film 25

With reference to FIG. 13, structural adhesive film 401 andfluoropolymer barrier layer 208 were provided and used to prepare abarrier modified surfacing film 25. More specifically, the followingmaterials were assembled and laminated as described in “GeneralLaminating” above. A 1 mil thick film of fluoropolymer film 208 wasjoined to one side of an 8 mil thick epoxy structural adhesive film 401which includes a non-woven polyester veil at 0.05 lbs./sqft available as3M™ Scotch-Weld™ Structural Adhesive Film AF 555M from 3M Company. Eachof the fluoropolymer films listed above was used to create a separatespecimen. All remaining liners and carriers were removed, includingpolyester films, providing a 9 mil thick barrier modified surfacing film25, which is a UV stable, fluid resistant surfacing film with astructural adhesive film and a thinner, cured fluoropolymer barrierlayer.

Multi-Layered Barrier Modified Surfacing Film 21

With reference to FIG. 5, a structural adhesive film 401 and apolyurethane/polycarbonate barrier layer 200 with attached 2 miltransparent polyester film 201 were provided and used to preparemulti-layered barrier modified surfacing film 21. More specifically, thefollowing materials were assembled and laminated as described in“General Laminating” above. A ½ mil thick polyurethane/polycarbonatebarrier layer 200 with attached 2 mil transparent polyester film 201 per“Polyurethane/Polycarbonate Barrier Layer” above was joined to one sideof an 8 mil thick epoxy structural adhesive film 401 which includes anon-woven polyester veil at 0.05 lbs./sqft available as 3M™ Scotch-Weld™Structural Adhesive Film AF 555M from 3M Company. All liners andcarriers except the 2 mil transparent polyester film 201 attached topolyurethane/polycarbonate barrier layer 200 were removed, providing a10.5 mil thick multi-layered barrier modified surfacing film 21, whichis a glossy UV blocking surfacing film with a high temperaturestructural adhesive film and thinner cured barrier layers.

Multi-Layered Barrier Modified Surfacing Film 26

With reference to FIG. 6, a structural adhesive film 402 and apolyurethane/polycarbonate barrier layer 200 with attached 2 miltransparent polyester film 201 were provided and used to prepare amulti-layered barrier modified surfacing film 26. More specifically, thefollowing materials were assembled and laminated as described in“General Laminating” above. A ½ mil thick polyurethane/polycarbonatebarrier layer 200 with attached 2 mil transparent polyester film 201 per“Polyurethane/Polycarbonate Barrier Layer” above was joined to one sideof a 13 mil thick epoxy structural adhesive film 402 which includes aknit nylon veil at 0.085 lbs./sqft available as 3M™ Scotch-Weld™Structural Adhesive Film AF 500K from 3M Company. All liners andcarriers except the 2 mil transparent polyester film 201 attached topolyurethane/polycarbonate barrier layer 200 were removed, providing a15.5 mil thick multi-layered barrier modified surfacing film (26). Aglossy transparent UV blocking surfacing film was obtained with a lowtemperature structural adhesive film and thinner cured barrier layers.

Multi-Layered Barrier Modified Conductive Surfacing Film 22

With reference to the FIG. 7, structural adhesive film 401, expandedaluminum foil 501 and polyurethane/polycarbonate barrier layer 200 withattached 2 mil transparent polyester film 201 were provided and used toprepare a multi-layered barrier modified conductive surfacing film 22.More specifically, the following materials were assembled and laminatedas described in “General Laminating” above. First a ½ mil thickpolyurethane/polycarbonate barrier layer 200 with attached 2 miltransparent polyester film 201 per “Polyurethane/Polycarbonate BarrierLayer” above was joined to one side of an 8 mil thick epoxy structuraladhesive film 401 which includes a non-woven polyester veil at 0.05lbs./sqft available as 3M™ Scotch-Weld™ Structural Adhesive Film AF 555Mfrom 3M Company. To the other side of the epoxy film was joined a 4 milthick expanded aluminum foil 501 available as Exmet 4AL8-080 fromDexmet. All liners and carriers except 2 mil transparent polyester film201 attached to the polyurethane/polycarbonate barrier layer 200 wereremoved, providing a 14.5 mil thick multi-layered barrier modifiedconductive surfacing film 22, which is a UV blocking conductivesurfacing film with a high temperature structural adhesive film,expanded metal foil and thinner, cured barrier layers.

Multi-Layered Barrier Modified Conductive Surfacing Film withViscoelastic Construction 23

With reference to FIG. 8, structural adhesive film 401 and expandedaluminum foil 501 and modified viscoelastic construction 10 wereprovided and used to prepare modified viscoelastic conductive surfacingfilm 23. More specifically, the following materials were assembled andlaminated as described in “General Laminating” above. First a 3 milthick modified viscoelastic construction 10 having barrier layers eitherside of a viscoelastic material was joined to one side of an 8 mil thickepoxy film 401 which includes a non-woven polyester veil at 0.05lbs./sqft available as 3M™ Scotch-Weld™ Structural Adhesive Film AF 555Mfrom 3M Company. To the other side of structural adhesive film 401 wasjoined a 4 mil thick expanded aluminum foil 501 available as Exmet4AL8-080 from Dexmet. All liners and carriers except a 2 mil transparentpolyester film (not shown) attached to barrier layer 200 were removed,providing a 15 mil thick modified visco-elastic conductive surfacingfilm 23 borne on 2 mil transparent polyester film (not shown). The UVblocking conductive vibration damping surfacing film was obtained with ahigh temperature structural adhesive film and expanded metal foil andvisco-elastic vibration damping material and thinner cured barrierlayers.

Multi-Layered Transparent EMI Shield Surfacing Film with ElectromagneticInterference (EMI) Shield of Alternating Functional Layers and BarrierLayers, 30

With reference to FIGS. 9 and 10, a 4 mil multi-layered transparent EMIshield surfacing film 30 was prepared as disclosed in U.S. patentapplication Ser. No. 12/255,025, filed on Oct. 30, 2007, based onpriority application 60/983,781 filed Oct. 21, 2008, the disclosure ofwhich is incorporated herein by reference. The film includes alternating15 nm thick layers of silver 510, 511, 512 and 70 nm thick layers ofacrylic barrier film 202, 203, 204 vapor deposited in a vacuum chamberonto a 4 mil transparent polyester film 207. This film provides highvisual transparency, substantially absorbs and reflects infraredwavelengths above 800 nm and ultraviolet wavelengths below 400 nm, andprovides approximately 44 dB of EMI shielding effectiveness at 100-1000MHz.

Conductive Multi-Layered Transparent EMI Shield Surfacing Film 31

With reference to FIG. 10, a multi-layered transparent EMI shieldsurfacing film 30 and an epoxy surfacing film with an expanded copperfoil 500 were provided and used to prepare a conductive multi-layeredtransparent EMI Shield surfacing film 31. More specifically, thefollowing materials were assembled and laminated as described in“General Laminating” above. The 4 mil multi-layered transparent EMIshield surfacing film 30 was joined with an 8 mil epoxy surfacing film500 which includes an expanded copper foil at 0.05 lbs./sqft, availableas 3M™ Scotch-Weld™ Low Density Composite Surfacing Film AF 325LS from3M Company, such that the 4 mil polyester film on the transparent EMIfilm was opposite the surfacing film. All liners and carriers wereremoved, providing a 12 mil thick conductive multi-layered transparentEMI shield surfacing film 31. The film provides high visualtransparency, substantially absorbs and reflects infrared wavelengthsabove 800 nm and ultraviolet wavelengths below 400 nm, and providesapproximately 44 dB of shielding effectiveness at 100-1000 MHz, and theconductive surfacing film provides a smooth sandable finish on the finalpart and conductivity for shielding and lightning protection.

Conductive Barrier Film 33

The following materials were assembled and laminated as described in“General Laminating” above: a fluoropolymer layer 209 (Dyneon™Fluoroplastic PVDF 11010/0000 polyvinylidene fluoride from Dyneon™ castto a film approximately 1 mil thick) was joined on one side with 0.22mil thick aluminum foil 502 (available from Republic Foil Inc.) to makeconductive barrier film 33.

Conductive Barrier Film 34

More specifically, was applied a 300 nm thick copper screen 505 waselectrodeposited and patterned as hexagons 300 um on a side, usingcircuit board printing processes, to one side of 2 mil transparentpolyester film 201 to make conductive barrier film 34.

Cured Examples

Cured Carbon Fiber Reinforced Plastic (CFRP) Laminate with ExpandedCopper Foil (ECF) and Surfacing Film, 60C (Comparative)

With reference to FIG. 1, epoxy resin impregnated carbon fiber fabric100 and an epoxy surfacing film with an expanded copper foil 500 wereprovided and used to prepare comparative composite specimen 60C. Morespecifically, the following materials were assembled and prepared asdescribed in “General Tooling and Bagging of a Composite Part” above.Applied first to the tool was epoxy surfacing film 500 which includes anexpanded copper foil at 0.05 lbs./sqft, available as 3M™ Scotch-Weld™Low Density Composite Surfacing Film AF 325LS from 3M Company. Lastlyapplied was 7 plies epoxy resin impregnated carbon fiber fabric 100,graphite fabric 3K-70-PW available as Cycom 970/PWC FT300 3K UT fromCytec. The curable resins in this assembly were cured as described in“High Pressure Curing of a Composite Part” above.

Cured laminate with EAF and adhesive film, 80C (Comparative) Withreference to FIG. 2, epoxy resin impregnated glass fiber fabric 101 andan epoxy adhesive film 401 and an expanded aluminum foil 501 wereprovided and used to prepare composite specimen 80C. More specifically,the following materials were assembled and prepared as described in“General Tooling and Bagging of a Composite Part” above. Applied firstto the tool was a 4 mil thick expanded aluminum foil 501 available asExmet 4AL8-080 from Dexmet. Then applied was an epoxy adhesive film 401which includes a non-woven polyester veil at 0.05 lbs./sqft available as3M™ Scotch-Weld™ Structural Adhesive Film AF 555M from 3M Company.Lastly applied was 6 plies of epoxy resin impregnated into wovenfiberglass 7781 fabric 101 available as 7781 38 F164-6 from Hexcel. Thecurable resins in this assembly were cured as described in “Low Pressure1½ Hour Curing of a Composite Part” above.

Cured Laminate with Adhesive Surfacing Film, 84C (Comparative)

With reference to FIG. 11, epoxy resin impregnated carbon fiber fabric100, 102 and an epoxy adhesive film 403 were provided and used toprepare a composite specimen. More specifically, the following materialswere assembled and prepared as described in “General Tooling and Baggingof a Composite Part” above. Applied first to the tool was an epoxyadhesive film 403 which includes a non-woven polyester veil available asSurface Master™ 905 from Cytec. Then applied was 1 ply epoxy resinimpregnated carbon fiber fabric 100, graphite fabric 3K-70-PW availableas Cycom 970/PWC FT300 3K UT from Cytec. Then applied was 8 plies epoxyresin impregnated unidirectional graphite fibers 102 available as P2353U19 152 from Toray. Lastly applied was 1 ply epoxy resin impregnatedcarbon fiber fabric 100, graphite fabric 3K-70-PW available as Cycom970/PWC FT300 3K UT from Cytec. The curable resins in this assembly werecured as described in “High Pressure Curing of a Composite Part” above.

Cured Core Laminate with 1 Barrier Film on Adhesive Film, 61

With reference to FIG. 3, epoxy resin impregnated glass fiber fabric101, glass fabric reinforced honeycomb core 103 and a barrier modifiedsurfacing film 20 were provided and used to prepare a composite specimen61. More specifically, the following materials were assembled andprepared as described in “General Tooling and Bagging of a CompositePart” above. Applied first to the tool was an 8.5 mil thick barriermodified surfacing film 20, prepared as described above, which wasapplied with the barrier layer closest to the tool and the adhesivelayer exposed. Then applied were 2 plies of epoxy resin impregnated intowoven fiberglass 7781 fabric 101 available as 7781 38 F164-6 fromHexcel. Then applied was a ½ inch thick glass fabric reinforcedhexagonal honeycomb core 103 which includes a heat-resistant phenolicresin, available as HRP-3/16-8.00 from Hexel. Lastly applied were 2 moreplies of epoxy resin impregnated into woven fiberglass 7781 fabric 101available as 7781 38 F164-6 from Hexcel. The curable resins in thisassembly were cured as described in “Low Pressure 1½ Hour Curing of aComposite Part” above.

Cured Core Laminate with 1 Barrier Film on Adhesive Film, 81

With reference to FIG. 4, epoxy resin impregnated glass fiber fabric101, glass fabric reinforced honeycomb core 103 and a barrier modifiedsurfacing film 24 were provided and used to prepare a composite specimen81. More specifically, the following materials were assembled andprepared as described in “General Tooling and Bagging of a CompositePart” above. Applied first to the tool was a 13.5 mil thick barriermodified surfacing film 24, prepared as described above, which wasapplied with the barrier layer closest to the tool and the adhesivelayer exposed. Then applied were 2 plies of epoxy resin impregnated intowoven fiberglass 7781 fabric 101 available as 7781 38 F164-6 fromHexcel. Then applied was a ½ inch thick glass fabric reinforcedhexagonal honeycomb core 103 which includes a heat-resistant phenolicresin, available as HRP-3/16-8.00 from Hexel. Lastly applied were 2 moreplies of epoxy resin impregnated into woven fiberglass 7781 fabric 101available as 7781 38 F164-6 from Hexcel. The curable resins in thisassembly were cured as described in “Low Pressure 1½ Hour Curing of aComposite Part” above.

Cured Core Laminate with 2 Barrier Films on Adhesive Film, 62

With reference to FIG. 5, epoxy resin impregnated glass fiber fabric101, glass fabric reinforced honeycomb core 103 and a multi-layeredbarrier modified surfacing film 21 were provided and used to prepare acomposite specimen 62. More specifically, the following materials wereassembled and prepared as described in “General Tooling and Bagging of aComposite Part” above. Applied first to the tool was a 10.5 mil thickmulti-layered barrier modified surfacing film 21, prepared as describedabove, which was applied with the barrier layers closest to the tool andthe adhesive layer exposed. Then applied were 2 plies of epoxy resinimpregnated into woven fiberglass 7781 fabric 101 available as 7781 38F164-6 from Hexcel. Then applied was a ½ inch thick glass fabricreinforced hexagonal honeycomb core 103 which includes a heat-resistantphenolic resin, available as HRP-3/16-8.00 from Hexel. Lastly appliedwere 2 more plies of epoxy resin impregnated into woven fiberglass 7781fabric 101 available as 7781 38 F164-6 from Hexcel. The curable resinsin this assembly were cured as described in “Low Pressure 1½ Hour Curingof a Composite Part” above.

Cured Core Laminate with 2 Barrier Films on Adhesive Film, 82

With reference to the FIG. 6, epoxy resin impregnated glass fiber fabric101, glass fabric reinforced honeycomb core 103 and multi-layeredbarrier modified surfacing film 26 were provided and used to prepare acomposite specimen 82. More specifically, the following materials wereassembled and prepared as described in “General Tooling and Bagging of aComposite Part” above. Applied first to the tool was a 15.5 mil thickmulti-layered barrier modified surfacing film 26, prepared as describedabove, which was applied with the barrier layers closest to the tool andthe adhesive layer exposed. Then applied were 2 plies of epoxy resinimpregnated into woven fiberglass 7781 fabric 101 available as 7781 38F164-6 from Hexcel. Then applied was a ½ inch thick glass fabricreinforced hexagonal honeycomb core 103 which includes a heat-resistantphenolic resin, available as HRP-3/16-8.00 from Hexel. Lastly appliedwere 2 more plies of epoxy resin impregnated into woven fiberglass 7781fabric 101 available as 7781 38 F164-6 from Hexcel. The curable resinsin this assembly were cured as described in “Low Pressure 1½ Hour Curingof a Composite Part” above.

Cured Laminate with EAF, Adhesive Film and 2 Barrier Films, 63

With reference to FIG. 7, epoxy resin impregnated glass fiber fabric 101and multi-layered barrier modified conductive surfacing film 22 wereprovided and used to prepare a composite specimen 63. More specifically,the following materials were assembled and prepared as described in“General Tooling and Bagging of a Composite Part” above. Applied firstto the tool was a 14.5 mil thick multi-layered barrier modifiedsurfacing film 22, prepared as described above, which was applied withthe expanded aluminum foil 501 closest to the tool and the barrierlayers exposed. Lastly applied were 6 plies of epoxy resin impregnatedinto woven fiberglass 7781 fabric 101 available as 7781 38 F164-6 fromHexcel. The curable resins in this assembly were cured as described in“Low Pressure 2 Hour Curing of a Composite Part” above.

Cured Laminate with EAF, Adhesive Film and a Barrier Layer Each Side ofVEM, 83

With reference to FIG. 8, epoxy resin impregnated glass fiber fabric 101and a modified visco-elastic conductive surfacing film 23 were providedand used to prepare a composite specimen 83. More specifically, thefollowing materials were assembled and prepared as described in “GeneralTooling and Bagging of a Composite Part” above. Applied first to thetool was a 15 mil thick modified visco-elastic conductive surfacing film23, prepared as described above, which was applied with the expandedaluminum foil 501 closest to the tool and the barrier layer exposed.Lastly applied were 6 plies of epoxy resin impregnated into wovenfiberglass 7781 fabric 101 available as 7781 38 F164-6 from Hexcel. Thecurable resins in this assembly were cured as described in “Low Pressure2 Hour Curing of a Composite Part” above.

Cured Laminate—CRFP with 1 Barrier Film, 85

With reference to FIG. 12, epoxy resin impregnated carbon fiber tape 100and a fluoropolymer surfacing film 208 were provided and used to preparea composite specimen 85. More specifically, the following materials wereassembled and prepared as described in “General Tooling and Bagging of aComposite Part” above. Applied first to the tool was a 1 mil thick filmof fluoropolymer 208. Then applied was 1 ply epoxy resin impregnatedcarbon fiber fabric 100, graphite fabric 3K-70-PW available as Cycom970/PWC FT300 3K UT from Cytec. Then applied was 8 plies epoxy resinimpregnated unidirectional graphite fibers 102 available as P2353U 19152 from Toray. Lastly applied was 1 ply epoxy resin impregnated carbonfiber fabric 100, graphite fabric 3K-70-PW available as Cycom 970/PWCFT300 3K UT from Cytec. Each type of fluoropolymer film 208 recitedabove was used to create a separate specimen. The curable resins in thisassembly were cured as described in “High Pressure Curing of a CompositePart” above.

Cured Laminate—CRFP with 1 Barrier Film on Adhesive Film, 86

With reference to FIG. 13, epoxy resin impregnated carbon fiber tape 100and a multi-layered surfacing film 25 were provided and used to preparea composite specimen 86. More specifically, the following materials wereassembled and prepared as described in “General Tooling and Bagging of aComposite Part” above. Applied first to the tool was a 9 mil thickbarrier modified surfacing film 25, prepared as described above, whichwas applied with the fluoropolymer barrier layer closest to the tool andthe adhesive layer exposed. Then applied was 1 ply epoxy resinimpregnated carbon fiber fabric 100, graphite fabric 3K-70-PW availableas Cycom 970/PWC FT300 3K UT from Cytec. Then applied was 8 plies epoxyresin impregnated unidirectional graphite fibers 102 available as P2353U19 152 from Toray. Lastly applied was 1 ply epoxy resin impregnatedcarbon fiber fabric 100, graphite fabric 3K-70-PW available as Cycom970/PWC FT300 3K UT from Cytec. Each multi-layered surfacing film 25,made with each type of fluoropolymer film 208 recited above, was used tocreate a separate specimen. The curable resins in this assembly werecured as described in “High Pressure Curing of a Composite Part” above.

Cured CFRP Laminate with Transparent EMI Shield, 70

With reference to the FIG. 9, epoxy resin impregnated carbon fiberfabric 100 and a multi-layered transparent EMI shield surfacing film 30were provided and used to prepare a composite specimen. Morespecifically, the following materials were assembled and prepared asdescribed in “General Tooling and Bagging of a Composite Part” above.Applied first to the tool was a 4 mil multi-layered transparent EMIshield surfacing film 30, prepared as described above, which was appliedwith the 4 mil polyester film 207 closest to the tool. Lastly appliedwas 7 plies epoxy resin impregnated carbon fiber fabric 100, graphitefabric 3K-70-PW available as Cycom 970/PWC FT300 3K UT from Cytec. Thecurable resins in this assembly were cured as described in “HighPressure Curing of a Composite Part” above.

Cured CFRP Laminate with ECF, Surfacing Film and Transparent EMI Shield,71

With reference to FIG. 10, epoxy resin impregnated carbon fiber fabric100 and a conductive surfacing film with a multi-layered EMI shield 31were provided and used to prepare a composite specimen 71. Morespecifically, the following materials were assembled and prepared asdescribed in “General Tooling and Bagging of a Composite Part” above.Applied first to the tool was a 12 mil conductive surfacing film with amulti-layered EMI shield 31, prepared as described above, which wasapplied with the 4 mil polyester film 207 closest to the tool. Lastlyapplied was 7 plies epoxy resin impregnated carbon fiber fabric 100,graphite fabric 3K-70-PW available as Cycom 970/PWC FT300 3K UT fromCytec. The curable resins in this assembly were cured as described in“High Pressure Curing of a Composite Part” above.

Cured CFRP Laminate with Conductive Fluoropolymer Barrier Layer, 72

With reference to FIG. 14, epoxy resin impregnated carbon fiber fabric100 and a conductive fluoropolymer barrier layer 513 were provided andused to prepare a composite specimen 72. More specifically, thefollowing materials were assembled and prepared as described in “GeneralTooling and Bagging of a Composite Part” above. Applied first to thetool was 1 mil thick conductive fluoropolymer barrier layer 513. Thenapplied was 1 ply epoxy resin impregnated carbon fiber fabric 100,graphite fabric 3K-70-PW available as Cycom 970/PWC FT300 3K UT fromCytec. Then applied was 8 plies epoxy resin impregnated unidirectionalgraphite fibers 102 available as P2353U 19 152 from Toray. Lastlyapplied was 1 ply epoxy resin impregnated carbon fiber fabric 100,graphite fabric 3K-70-PW available as Cycom 970/PWC FT300 3K UT fromCytec. Each type of conductive fluoropolymer barrier layer 513 recitedabove was used to create a separate specimen. The curable resins in thisassembly were cured as described in “High Pressure Curing of a CompositePart” above.

Cured CFRP Laminate with Conductive Foil on a Barrier Layer, 74

With reference to FIG. 15, epoxy resin impregnated carbon fiber fabric100 and a conductive surfacing film 33 were provided and used to preparea composite specimen 74. More specifically, the following materials wereassembled and prepared as described in “General Tooling and Bagging of aComposite Part” above. Applied first to the tool was a 1 mil conductivesurfacing film 33, prepared as described above, which was applied withthe fluoropolymer barrier layer closest to the tool and the metal layerexposed. Lastly applied was 8 plies epoxy resin impregnated carbon fiberfabric 100, graphite fabric 3K-70-PW available as Cycom 970/PWC FT300 3KUT from Cytec. The curable resins in this assembly were cured asdescribed in “High Pressure Curing of a Composite Part” above.

Cured CFRP Laminate with Conductive Surfaced Barrier Layer, 75

With reference to FIG. 16, epoxy resin impregnated carbon fiber fabric102 and a conductive surfacing film 504 were provided and used toprepare a composite specimen 75. More specifically, the followingmaterials were assembled and prepared as described in “General Toolingand Bagging of a Composite Part” above. Applied first to the tool wasconductive surfacing film 504, available from Cima NanoTech, which is a2 mil transparent polyester film 201 coated on one side with silvernanoparticles 503 and dried to form a conductive surface. Conductivesurfacing film 504 was applied with the polyester film 201 closest tothe tool and the conductive layer 503 exposed. Lastly applied was 8plies epoxy resin impregnated unidirectional graphite fibers 102available as P2353U 19 152 from Toray. The curable resins in thisassembly were cured as described in “High Pressure Curing of a CompositePart” above.

Cured CFRP Laminate with Conductive Surfaced Barrier Layer, 76

With reference to FIG. 17, epoxy resin impregnated carbon fiber fabric102 and a conductive surfacing film 34 were provided and used to preparea composite specimen 76. More specifically, the following materials wereassembled and prepared as described in “General Tooling and Bagging of aComposite Part” above. Applied first to the tool was a 2 mil transparentpolyester film with a 300 nm thick copper screen 34, prepared asdescribed above, which was applied with the polyester surface closest tothe tool and the conductive face exposed. Lastly applied was 8 pliesepoxy resin impregnated unidirectional graphite fibers 102 available asP2353U 19 152 from Toray. The curable resins in this assembly were curedas described in “High Pressure Curing of a Composite Part” above.

Evaluation

After curing, coupons from example 60, 80C, 84C, 61, 81, 62, 82, 63, 83,85, 86, 70, and 71 were inspected for surface defects. The results fromthese observations are reported in Table 1.

Example 61, 81, 62, 82, 85, 86, 70, and 71 all included one or morebarrier layers with UV absorbers or stabilizers. Example 63 includedbarrier layers between the conductive metal mesh and the fiberreinforcement of the composite lay-up. Example 83 included barrierlayers and a viscoelastic vibration damping layer between the conductivemetal mesh and the fiber reinforcement of the composite lay-up.

TABLE 1 Minimum Distance Pin Fiber to Mesh to Resin Ex. holes PitsSurface Surface Mesh to Fiber Migration 60C yes yes n/a not not notevaluated evaluated evaluated 80C yes yes n/a mesh exposed meshcontacting yes <1> <2> fibers 84C yes no n/a n/a n/a not evaluated 61 nono not n/a n/a not evaluated evaluated 81 no no thickness of n/a n/a notbarrier layer evaluated 62 no no not n/a n/a not <3> evaluated evaluated82 no no not n/a n/a not <3> evaluated evaluated 63 no yes n/a variablebut thickness of no not exposed barrier layer 83 no yes n/a variable butthickness of no not exposed barrier layer <4> 85 no no n/a n/a n/a notevaluated 86 no no n/a n/a n/a not evaluated 70 no no n/a n/a n/a notevaluated 71 no no not not not not evaluated evaluated evaluatedevaluated <1> Surfacing film migrated at least into the second ply offiberglass fabric. <2> The pin-holes extended through the layer of metalmesh and the first layer of fiberglass fabric into the second layer offiberglass fabric. <3> Surface glossy exhibiting spectral reflectance.<4> The conjoined barrier layers and visco-elastic damping polymerappear constant thickness and assumed an undulating path between themetal mesh and the first layer of fiberglass fabric.After curing, coupons from example 84C, 85, 86, 72, 74, 75, and 76 wereexamined for selected electromagnetic properties of the coupons andresistance to paint strippers. The observations are reported in Table 2.

TABLE 2 Change in Paint Adhesion per Paint Adhesion per EMI SurfaceStatic Pencil Hardness ASTM D3359**** ASTM D3359**** ShieldingConductivity* Dissipation** per ASTM Before exposure After 24 hrexposure Efficiency Ex. (Ω/square) (seconds) 3363**** to paintstripper*** to paint stripper*** (dB) ***** 84C 10¹⁶ not >8 5B 3B 54evaluated 85 not not <2 5B for 5B for PVDF not evaluated evaluated PVDFevaluated 86 not not <2 5B for 5B for PVDF not evaluated evaluated PVDFevaluated 72 10¹⁵-<10⁷    <0.01 <2> not   4B<3>   5B<3> not evaluatedevaluated 74 not not not not not 57 evaluated evaluated evaluatedevaluated evaluated 75 10¹⁵ <0.01 not not not 57 evaluated evaluatedevaluated 76 10¹¹ <0.01 not not not 58 evaluated evaluated evaluated*per ASTM D257 **Time to dissipate 90% of 5k Volts measured in anElectro Tech systems model 406C Static Decay Meter. ***Measured afterapplying one coat PRC-Desoto CA7501HS primer. ****Measured before andafter saturating the surface for 24 hours with a paint stripper such asCee-Bee ® E2012A available from McGean at a rate of 0.2 grams/cm². ASTMD3359 Adhesion Classifications are as recited in Table 3.

TABLE 3 Adhesion Amount of Area Classification Removed 0B >65% 1B35%-65% 2B 15%-35% 3B  5%-15% 4B <15% 5B None ***** ElectromagneticInterference (EMI) Shielding Efficiency measured from 1 to 18 GHz perIEEE299 using a dual chamber configuration. <2> Evaluated on the PVDFwith multiwalled carbon nano-tubes only. <3> Evaluated on the THV withmultiwalled carbon nano-tubes only.

Various modifications and alterations of this disclosure will becomeapparent to those skilled in the art without departing from the scopeand principles of this disclosure, and it should be understood that thisdisclosure is not to be unduly limited to the illustrative embodimentsset forth hereinabove.

We claim:
 1. A method of making a fiber reinforced resin matrixcomposite laminate comprising the steps of: a) providing a curable fiberreinforced resin matrix comprising a curable resin matrix; b) providinga surfacing construction comprising: i) at least one barrier layer; andii) at least one curable adhesive layer; c) providing a tool having ashape which is the inverse of the desired shape of the laminate; e)laying up the surfacing construction and the curable fiber reinforcedresin matrix in the tool, with the surfacing construction in contactwith the tool and with at least one curable adhesive layer in contactwith the curable fiber reinforced resin matrix; and f) curing thecurable resin matrix and curable adhesive layer to make a fiberreinforced resin matrix composite laminate; wherein the barrier layer(s)have a composition different from that of the curable adhesive layer(s)and the barrier layer(s) have a composition different from that of thecured resin matrix.
 2. The method according to claim 1 wherein at leastone curable adhesive layer has a composition different from that of thecurable resin matrix.
 3. The method according to claim 1 wherein atleast one barrier layer is substantially impermeable to organicsolvents.
 4. The method according to claim 1 wherein at least onebarrier layer is substantially impermeable to water, organic solventsand gasses.
 5. The method according to claim 1 wherein the surfacingconstruction additionally comprises: iii) at least one electricallyconductive layer.
 6. The method according to claim 1 wherein thesurfacing construction additionally comprises: iv) at least one EMIshield layer.
 7. The method according to claim 1 wherein the surfacingconstruction additionally comprises: v) at least one UV protectionlayer.
 8. The method according to claim 1 wherein the surfacingconstruction additionally comprises: vi) at least one viscoelastic layerhaving a peak damping ratio (Tan δ) of at least 1.0 as measured in shearmode by DMTA at 10 Hz.
 9. The method according to claim 1 wherein thesurfacing construction comprises a barrier layer comprising afluoropolymer.
 10. The method according to claim 1 wherein the surfacingconstruction comprises a barrier layer comprising a non-perfluorinatedfluoropolymer.
 11. The method according to claim 1 wherein the surfacingconstruction comprises a curable adhesive layer comprising an epoxyadhesive and a dicyandiamide curative.
 12. The method according to claim1 wherein the surfacing construction comprises a curable adhesive layercomprising an epoxy adhesive and a dicyandiamide curative and a barrierlayer comprising a non-perfluorinated fluoropolymer.
 13. The methodaccording to claim 1 wherein the surfacing construction comprises acurable adhesive layer comprising an epoxy adhesive and curative whichcontains no amine-containing curative.
 14. The method according to claim1 wherein at least one curable adhesive layer has a compositiondifferent from that of the curable resin matrix.
 15. The methodaccording to claim 1 wherein at least one curable adhesive layer has acomposition which is the same as that of the curable resin matrix. 16.The method according to claim 1 wherein at least one curable adhesivelayer is the curable resin matrix.
 17. The method according to claim 1wherein at least one curable adhesive layer is not the curable resinmatrix.